I made a "hard" stop the other day and then noticed my brakes did not release. To make a long story short, ...My brakes work just fine under normal stops, however, when I apply the brakes hard my rear brakes wont release "unless" I press the brake peddle hard again wile the truck is stopped it then will release the rear brakes and everything is fine again. So I been purposely stopping hard to see if it happens all the time , and it does..so I just press the brake peddle hard again and it releases. I am not stopping hard enough to activate the ABS system, and I did replace the "brake master cylinder" about two months ago. This truck is a 2000 and has 57,000 miles on it. It does have Hydro boost and the truck does not get driven much. Any HELP please...Proportioning valve ? .. Master cylinder ?

 

I replaced the brake master cylinder today and it DID NOT solve my problem. It still will not release REAR brake pressure only when stopping hard. The only way I get them to release is to press the brake pedal even harder and they release. PLEASE HELP !!!

 

Ok....It's not fixed, BUT, I do know whats wrong with it. I pulled the ABS 60amp fuse and now the rear brakes DO release after a hard stop. What is so confusing, is that the anti lock brakes were working. I heard NO abnormal noise coming from the ABS module and it would work when stopping on our snow covered roads tonight but it would NOT release the back brakes till I pushed even harder on the peddle wile the truck was still stopped then they would release, and brake peddle "feel" always felt good/normal.